½ cup minced fresh ginger (from a 4- to 5-inch piece)
3 cloves garlic, minced
1 tbsp tamarind paste, dissolved in ½ cup red wine vinegar
¼ cup packed brown sugar
1 can (14.5 ounces) whole tomatoes, roughly chopped, with juice
Kosher salt and fresh cracked black pepper, to taste
In a heavy-bottomed sauté pan, heat the oil over medium high heat. Add the onion and cook, stirring occasionally until softened, about 5 minutes. Turn the heat to low and add the ginger and garlic. Continue cooking, stirring occasionally, until the onion is soft and transparent, about 15 minutes.
Turn the heat to medium high and add the vinegar-tamarind mixture and the sugar. Cook, stirring frequently, for 5 minutes, until the mixture is slightly thickened. Add the tomatoes, turn the heat to low, and simmer for 30 minutes. Season with salt and pepper.